1 definition
by
TEX37

Statement used to express regret and or fear about the current situation of an amorous or once amorous relationship. It generally means that the person who is expressing himself/herself has a deep emotional bond with their current mate, but that bond is possibly/probably not strong enough to merit a lifetime, or long-term commitment. Usually, there is either some dissatisfaction, disappointment, or confusion on the part of the person using this statement.

Example (interchangeable):

Woman: Why can't we be together?
Man: I love you, but I'm not in love with you.
Woman: What does that mean?
Man: It means that I need something in my life that being with you is just not able to provide. If you need anything, I'm there, but we aren't working.